FormalConjectures/Books/BugeaudDistributionModuloOne/IntDistanceDistribution.lean
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5 declarations, 4 contain sorry, 0 declared as axioms
Bugeaud Collection of Conjectures and Open Questions: Fractional Parts of Powers
Chapter 10 of the book collects open questions. This file formalizes Problems 10.1, 10.2, 10.3 and the unnumbered conjecture by Waldschmidt.
References:
- [Bug12] Bugeaud, Yann. "Distribution modulo one and Diophantine approximation." Vol. 193. Cambridge University Press, 2012. Chapter 10.
- [Har19] Hardy, Gr H. "A problem of Diophantine approximation." J. Indian Math. Soc 11 (1919): 162-166.
- [Kok45] Koksma, J. F. "Sur la théorie métrique des approximations diophantiques." Indag. Math 7 (1945): 54-70.
- [Mah53] Mahler, Kurt. "On the approximation of logarithms of algebraic numbers." Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences 245.898 (1953): 371-398.
- Wal03 Waldschmidt, Michel. "Linear independence measures for logarithms of algebraic numbers." Diophantine Approximation: Lectures given at the CIME Summer School held in Cetraro, Italy, June 28–July 6, 2000. Berlin, Heidelberg: Springer Berlin Heidelberg, 2003. 249-344.
Imports (1)
- theorem
Bugeaud01.problem_10_1Problem 10.1 sorry line 52 sourceSource documentation
Problem 10.1. Are there a transcendental number $\alpha$ and a positive real number $\xi$ such that $\lVert \xi \alpha^n \rVert$ tends to~$0$ as~$n$ tends to infinity? [Har19] (Trivial for $|\alpha| < 1$)
depends on sorry what this means
Statement uses:
Iff,True,Exists,Real,And,LT.lt,OfNat.ofNat,abs,Transcendental,Rat,Filter.Tendsto,Nat, distToNearestInt,HMul.hMul,HPow.hPow,Filter.atTop,nhdsProof uses:
sorryAx,Lean.Name,Bool.false,Lean.Name.num,Lean.Name.str,Lean.Name.anonymous57 instances, coercions and auxiliary constants left out.
Tactic trace: 1 steps
Open to load the checked before-and-after goal states.
theorem problem_10_1 : answer(sorry) ↔ ∃ (α ξ : ℝ), 1 < |α| ∧ Transcendental ℚ α ∧ 0 < ξ ∧ Filter.Tendsto (fun n : ℕ ↦ distToNearestInt (ξ * α ^ n)) Filter.atTop (nhds 0) := by …Mentions: distToNearestInt
- theorem
Bugeaud01.problem_10_2Problem 10.2 sorry line 62 sourceSource documentation
Problem 10.2. To prove that $\lVert e^n \rVert$ does not tend to 0 as n tends to infinity.
depends on sorry what this means
Statement uses:
Not,Filter.Tendsto,Nat,Real, distToNearestInt,Real.exp,Filter.atTop,nhds,OfNat.ofNatProof uses:
sorryAx,Lean.Name,Bool.false,Lean.Name.num,Lean.Name.str,Lean.Name.anonymous17 instances, coercions and auxiliary constants left out.
Tactic trace: 1 steps
Open to load the checked before-and-after goal states.
theorem problem_10_2 : ¬ Filter.Tendsto (fun n : ℕ ↦ distToNearestInt (Real.exp n)) Filter.atTop (nhds 0) := by …Mentions: distToNearestInt
- theorem
Bugeaud01.problem_10_3Problem 10.3 sorry line 71 sourceSource documentation
Problem 10.3. To prove that there exists a positive real number~$c$ such that $\lVert e^n \rVert > e^{−cn}$, for every~$n \ge 1$. Posed by Mahler [Mah53].
depends on sorry what this means
Statement uses:
Exists,Real,And,LT.lt,OfNat.ofNat,Nat,LE.le,Real.exp,HMul.hMul,Neg.neg, distToNearestIntProof uses:
sorryAx,Lean.Name,Bool.false,Lean.Name.num,Lean.Name.str,Lean.Name.anonymous20 instances, coercions and auxiliary constants left out.
Tactic trace: 1 steps
Open to load the checked before-and-after goal states.
theorem problem_10_3 : ∃ c : ℝ, 0 < c ∧ ∀ n : ℕ, 1 ≤ n → Real.exp (-c * n) < distToNearestInt (Real.exp n) := by …Mentions: c, distToNearestInt
- theorem
Bugeaud01.waldschmidtWaldschmidt [Wal03] conjectured that a stronger result holds, namely that there exists a positive real number~$c$ such that $\lVert e^n \rVert > n^{-c}$ for every~$n \ge 2$ sorry line 84 sourceSource documentation
Waldschmidt [Wal03] conjectured that a stronger result holds, namely that there exists a positive real number~$c$ such that $\lVert e^n \rVert > n^{-c}$ for every~$n \ge 2$. This is supported by metrical results [Kok45].
Note: the bound $n^{-c}$ equals $1$ when $n = 1$ for all $c$, while the distance to the nearest integer is always at most $1/2$, so the conjecture must start at $n \ge 2$.
depends on sorry what this means
Statement uses:
Exists,Real,And,LT.lt,OfNat.ofNat,Nat,LE.le,HPow.hPow,Neg.neg, distToNearestInt,Real.expProof uses:
sorryAx,Lean.Name,Bool.false,Lean.Name.num,Lean.Name.str,Lean.Name.anonymous20 instances, coercions and auxiliary constants left out.
Tactic trace: 1 steps
Open to load the checked before-and-after goal states.
theorem waldschmidt : ∃ c : ℝ, 0 < c ∧ ∀ n : ℕ, 2 ≤ n → (n : ℝ) ^ (-c) < distToNearestInt (Real.exp n) := by …Mentions: c, distToNearestInt
- theorem
Bugeaud01.problem_10_3_of_waldschmidtWaldschmidt's conjecture is stronger than Mahler's: since $\log n \le n$ for $n \ge 1$, the polynomial lower bound $n^{-c}$ dominates the exponential lower bound $e^{-cn}$ line 95 sourceSource documentation
Waldschmidt's conjecture is stronger than Mahler's: since $\log n \le n$ for $n \ge 1$, the polynomial lower bound $n^{-c}$ dominates the exponential lower bound $e^{-cn}$. For the $n = 1$ case (not covered by Waldschmidt's $n \ge 2$), we choose a larger constant using the numerical bound $\lVert e \rVert = 3 - e > 0$.
standard axioms: Classical.choice, Quot.sound, propext what this means
Statement uses:
Exists,Real,And,LT.lt,OfNat.ofNat,Nat,LE.le,HPow.hPow,Neg.neg, distToNearestInt,Real.exp,HMul.hMulProof uses:
Eq.mpr,abs,HSub.hSub,id,Eq,congrArg,round,Eq.trans,Int,Real.round_exp_one_eq_three,Int.cast_ofNat,Ne,propext,abs_pos,Not.intro,Mathlib.Tactic.Linarith.lt_irrefl,Eq.mp,HAdd.hAdd,Mathlib.Tactic.Ring.of_eq,Mathlib.Tactic.Ring.Common.add_congrand 111 more160 instances, coercions and auxiliary constants left out.
Tactic trace: 33 steps
Open to load the checked before-and-after goal states.
theorem problem_10_3_of_waldschmidt (h : type_of% waldschmidt) : type_of% problem_10_3 := by …
Mentions: Bugeaud01.waldschmidt, Bugeaud01.problem_10_3